Field of the Invention
The present invention relates to an optical scanning device that scans a target surface with a laser beam.
Description of the Related Art
An optical scanning device used in an image forming apparatus of an electrophotographic recording type, such as a laser printer, deflects a laser beam emitted by a light source with an optical deflector and scans a photosensitive member in accordance with an image signal. Typically, an optical scanning device includes an electronic component, such as a laser driver for driving a light source or a motor driver for driving an optical deflector, and the electronic component is covered by a case and a lid for the optical scanning device. In addition, in order to reduce the cost, a case or a lid is typically fabricated by shaping resin with a mold. A case or a lid needs to be dimensioned with high precision. Therefore, when resin is molded, the surface roughness of the mold is reduced in order to increase the flowability or the releasability of resin, and thus the precision of the component is improved. Since the surface roughness of the mold is low, the surface roughness of the molded product is also low, and the molded product may be glossy depending on the material.
Japanese Patent Laid-Open No. 2004-279611 discloses a configuration in which the inner surface of the case is roughened so that a deflected and scanned laser beam is not reflected by the inner surface of the case.
In the meantime, when dust or the like enters the interior of an optical scanning device, the dust may block a laser beam, which leads to a problem in that a portion corresponding to the blocked laser beam is missing in an image. Therefore, when transporting an optical scanning device that is to be embedded into an image forming apparatus, the optical scanning device is transported while being covered tightly or individually packaged in a bag in order to prevent dust from entering the optical scanning device.
However, a case or a lid constituting the optical scanning device can be electrified as an assembly operator comes into contact with the optical scanning device while embedding the optical scanning device into the image forming apparatus. As a result, an electrostatic discharge (ESD) may occur in an IC, such as a laser driver, a motor driver, or a BD sensor, and the IC can be damaged. In addition, there is a mode in which static electricity flows from a charged case or lid when connecting a cable for a motor or a laser and a driver IC for the motor or the laser is damaged. Furthermore, in a case in which an optical scanning device is individually packaged, electrification by peeling may occur between the bag and the case or the id when removing the optical scanning device from the bag, and a driver IC for a motor or a laser can be damaged in a similar manner. Typically, a countermeasure is taken by carrying out a de-electrification operation with the use of an ionizer or the like, but it takes time to carry out de-electrification in a stable manner. In addition, although the surface potential can be reduced, the potential of the interior of the case that is not exposed to the de-electrifying air cannot be reduced, and thus such a countermeasure has little effect on the ESD when the aforementioned cable is connected.